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      Wire colors
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      <h1>
        Wire colors
      </h1>
      <p>
        We are now in a position to summarize the full rainbow of colors that Logisim wires can take on. The following little circuit illustrates all of them at once.
      </p>
      <p align="center">
        <img class="notscal" src="../../../../img-guide/bundles-colors.png" alt="#########">
      </p>
      <ul>
        <li>
          <p>
            <strong>Gray:</strong> The wire's bit width is unknown. This occurs because the wire is not attached to any components' inputs and outputs. (All inputs and outputs have a defined bit width.)
          </p>
        </li>
        <li>
          <p>
            <strong>Blue:</strong> The wire carries a one-bit value, but nothing is driving a specific value onto the wire. We call this a <em>floating</em> bit; some people call it a <em>high-impedance</em> value. In this example, the component placing a value onto the wire is a three-state pin, so it can emit this floating value.
          </p>
        </li>
        <li>
          <p>
            <strong>Dark green:</strong> The wire is carrying a one-bit 0 value.
          </p>
        </li>
        <li>
          <p>
            <strong>Bright green:</strong> The wire is carrying a one-bit 1 value.
          </p>
        </li>
        <li>
          <p>
            <strong>Black:</strong> The wire is carrying a multi-bit value. Some or all of the bits may not be specified.
          </p>
        </li>
        <li>
          <p>
            <strong>Red:</strong> The wire is carrying an error value. This often arises because a gate cannot determine the proper output, perhaps because it has no inputs. It could also arise because two components are trying to send different values onto the wire; this is what happens in the above example, where one input pin places 0 onto the wire while another places 1 onto the same wire, causing a conflict. Multi-bit wires will turn red when any of the bits carried are error values.
          </p>
        </li>
        <li>
          <p>
            <strong>Orange:</strong> The components attached to the wire do not agree in bit width. An orange wire is effectively "broken": It does not carry values between components. Here, we've attached a two-bit component to a one-bit component, so they are incompatible.
          </p>
        </li>
        <li>
          <p>
            <strong>Green-Fuchsia:</strong> This color scheme indicates that the wire was selected with the tool <b class=propertie>push</b> (<img class="icontxt" src="../../../../icons/1616/toolpoke.png" alt="#########">). This allows us to know the way and also the indication of the state of the line will be displayed in a small bubble and it also allows to follow a connection in a complex scheme.
          </p>
        </li>
      </ul>
      <p>
        <b>Next:</b> <a href="fet-autolabel.html">Self numbered label</a>.
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